And out of those "hundreds" only a handful of them are actually popular and progressing innovation...
As someone who's distro hopped across a wide verity of distros, the fundamentals are more less the same across all of them. Just go with a popular distro with good documentation and you'll be fine. If you've learned enough from mint to feel comfortable tackling Arch Linux, then the documention (e.g. ArchWiki) will be your strongest asset.